Apparatus for mechanical treatment of material



July 17, 1962 H. BEHRENS 3,

APPARATUS FOR MECHANICAL TREATMENT OF MATERIAL Filed. July es, 1959INVENTDP HEINZ BENRENS BY WM w. 3am,

ATTORN Er United States Pater 3,044,623 APPARATUS FOR MECHANICALTREATMENT OF MATERIAL Heinz Behrens, 20 Deiselkulrnerweg, Schwarzenfeld,Oberpfalz, Germany Filed July 6, 1959, Ser. No. 825,014 7 Claimspriority, application Germany Aug. 21, 1953 1 Claim. (Cl. 209-275) Thepresent invention relates to apparatus for carrying out such method. Asan example of such treatment reference may be made to the screening ofmaterials, which are capable of being poured or are of a granular orpulverulent nature or in the form of a liquid suspension, or to themixing together of different materials.

The invention provides such apparatus which is greatly superior to theapparatus heretofore employed, as regards the output achieved calculatedin relation to the necessary dimensions of the apparatus employed, andalso as regards accuracy of the treating process, for example thepossibility of regulation of the process, or the like.

In the apparatus according to the invention, a rolling motion isimparted to the material by the application of vibrations to thereceptacle containing the material. By suitable design of the receptaclea plurality of such rolling movements can be set up parallel to oneanother. If the receptacle accommodating a material to which a rollingmotion is thus imparted is given the form, for example, of a screen,there is obtained in a very brief space of time a separation of thematerial into its components, which separation is more complete andeifective than that of previous methods for a given size of screen mesh.Similarly the combining or mixing of different substances is alsoconsiderably improved if vibrations are imparted to them to give them arolling motion. Upon the addition of further substances there isobtained an almost ideally complete mixing, which is a considerableimprovement on mixing methods known heretofore. The mechanicaltreatment, for example screening or mixing, may also be carried out stepby step; a classification in various degrees of fineness may be obtainedby a screening operation and a mixture comprising a plurality of initialmaterials by a mixing operation.

In the apparatus according to the invention troughlike channels arepreferably employed which, by means of vibration generators, are givenshaking movements substantially transverse to the axis of the channel.In these trough-like channels there are then produced two streams ofmaterials rolling in opposition to one another.

A pure rolling motion of the material located in the channel may also besuperposed on a conveying motion longitudinally of the channel. Theconveyance of the material may take place by inclining the channel or bymeans of vibrations having a component in the direction of conveyance ofthe material. This latter device has the advantage of obviatingdifferences in height between the intake and discharge points of thechannel. In this connection it has been found that when superposingtransverse and longitudinal vibrations the separation or mixing ofmaterial in the channel is considerably improved. In the screening ofmaterials it is of particular advantage if the vibration componentsbringing about the conveyance of the material are directed obliquely tothe surface on which treatment of the material takes place, for exampleat an angle of approximately 15 to the perpendicular at the screensurface, as in this case the vertical component of these vibrationsgreatly assists the screening operation. The vibrations can be impartedto the receptacle for the material under treatment by means of one ormore vibraration generators, and the frequencies of the transversevibrations producing the rolling streams of material and those of thevibrations effecting the conveyance and assistice Patented July 17, 1962 ing the treating operation may be equal to or different from oneanother. By varying the frequency or amplitude of these vibrations it isalso possible to, regulate the speed ofthe rolling action and the rateof conveyance as may be desired in a particular case.

Various forms of apparatus according to the invention are showndiagrammatically by way of example in the accompanying drawings inwhich:

FIGURE 1 shows diagrammatically how two rolling streams of material areformed in a channel;

FIGURES 2a and 2b show, respectively in cross section and in elevation,a curved channel which is perforated or is furnished with a screenattachment and is capable of being vibrated transversely to thedirection in which. the material is conveyed;

FIGURES 3a and 3b show, respectively in perspective and in elevation, aninclined screen channel of the above kind for conveying coarse materialunder gravity; and

FIGURES 4a and 4b show a horizontal or substantially horizontal channel,to which there are applied simultaneously by means of one singleunbalanced mass both a vibration component transverse to the directionof conveyance and a component in that direction.

Referring to FIGURE 1, there is' suspended between uprights 1 a channel2, in which the material, in the form of two part-streams 4 and 5, has agyratory and possibly also a helical advancing motion imparted to it bymeans of a shaking devicewhich is not shown in detail, for example arotating unbalanced mass 3, which may be mounted on the end of anelectric motor shaft (not shown).

FIGURES 2 to 4 show the apparatus according to the invention applied toscreening operations, FIGURESQa and 2b being a cross-sectional view anda partial elevational view respectively of a channel 7 furnished withperforations 6. The reference numeral 8 indicates diagramatically theforce producing the transverse vibrations.

The profile shown may naturally be modified according to circumstances,and in particular its shape in cross section may approach more or less asemi-circle.

In FIGURES 3a and 3b, which will be understood without furtherdescription, the channel is shown inclined towards the discharge end.

FIGURES 4a and 4b show in front view and in elevation a horizontalchannel 9, to which a vibratory motion is imparted by means of a singlevibration generator 12 which, as shown, is arranged above the channel 9,for example on the side flanges 10 and 11 thereof. The oscillation ofthe channel 9 is most satisfactory with the oscillator running at about3000 cycles per minute. These vibrations have a component in thedirection of the longitudinal axis of the channel and also transverselythereto so that each point of the channel is given a circular orelliptical movement: the channel is mounted on wooden or steel springsor bars 15, which are elastic in a plane perpendicular to thelongitudinal axis of the channel 9.

For this purpose the vibration generator is arranged at an angle a tothe perpendicular, so that the vibrations produced possess a verticalcomponent in addition to their horizontal component. When the angle a is0 the vertical component is zero, whilst the horizontal componentperpendicular to the longitudinal axis of the channel is a maximum. Theangle 0: can be varied between 0 and a maximum of but over the whole ofthis range the horizontal vibration component perpendicular to thechannel axis is the maximum. Variation of the angle on does however varythe horizontal component in the direction of the longitudinal axis andwhen 0: equals 90 it is zero. Accordingly it is possible by Varying theangle a to vary not only the rate of advance of the material in thelongitudinal direction of the channel, but also the height to which thematerial is lifted, so that it is readily possible to ascertain byexperiment the optimum angle which is to be dependent on the material tobe screened. The same is naturally also true to a mixing operation, theangle a being adapted to the materials being mixed. The two streams ofmaterials rolling in opposition to each other are produced by arrangingthe axis of the unbalanced mass of the vibration generator 12essentially perpendicularly to the horizontal and essentially in thecenter of the trough 9.

The form of the receptacle for the material is naturally not limited toa channel-like construction, and the surface employed for screening ormixing purposes may have any desired form; a channel-like form has,however, been found the most suitable.

If desired, a plurality of channels can be arranged side by side, andthey may be given such vibrations as are necessary for screening ormixing by means of common vibration generators or generators which arecoupled together in suitable fashion.

The channel may be either rigidly orresiliently constructed. It may havethe form of a semi-circular or of a complete pipe, in which connectionit is merely necessary to ensure that the channel formation does notprevent the occurrence of the gyratory part-streams of materialmentioned above.

As vibration generating means there may be employed unbalanced devicesor electro-magnetic or electro-static vibration means, and the vibrationgenerators may be so arranged that instead of producing substantiallyregular vibrations the form of vibration itself is capable of beingvaried in many different ways. Particularly for mixing operations, butalso if desired for screening purposes, the channel may be heated orelectrically charged, heating or electrical charge may he allowed totake effect substantially only on the surface portions contacting thematerials to be mixed or screened.

The two counter-rotating streams of material are established in the bestmanner with a channel having a semicircular cross-section, the diameterof which is between and 200 mm., whereby this trough-like receptacle isabout 800 mm. long. The frequency of the vibration imparted to thereceptacle is between and 75 periods per second, whereas the amplitudeof such vibrations lies between 0.5 and 2 mm. The size of granulation ofthe material to be treated is between 0.3 mm. and 4 mm. and determinesto some extent the frequency and the amplitude of the vibration togetherwith other features of the material as humidity, temperature and otherphysical properties. But it is possible to a man skilled in the artwithout invention to adapt the frequency and amplitude of the vibrationsto these properties of the material by simple alterations of the speedof the motor driving the unbalanced mass creating the vibrations.

Example A mixture of chamotte has been screened up to a size of 0.3 to 1mm. in trough-like receptacles having semicircular cross-section. Thediameters of these receptacles were about 25 mm. Eleven of such troughshave been combined to a solid combined construction with a length of 800mm. This construction has been vibrated with a frequency of 48 periodsper second and an amplitude of 1.2 mm. The throughput was kg. per hourand channel, Le. 1100 kg. per hour for the whole construction. Thediameter of the screening holes was 1 mm. On the end of the channelsonly coarse material in small amount was present.

As will be apparent from the above description, the invention is notlimited to the embodiments above described, in detail and illustrated inthe drawings, and numerous modifications may be made without departingfrom the fundamental idea of the invention as defined in the appendedclaim.

The invention may in particular he applied to the conversion of ceramicsubstances into a thixotropic condition.

This application constitutes a continuation-in-part of my copendingapplication Serial No. 450,867, now abandoned, filed August 19, 1954,and entitled Methods and Apparatus for Mechanical Treatment of Material.

What I claim is:

Apparatus for mechanically treating finely divided material comprising ahorizontally extending elongate conduit of arcuate trough-likecross-section formed of deformable perforated material, resilientsupport means for supporting said conduit and enabling movement in adirection parallel to the longitudinal axis thereof and in a planesubstantially perpendicular to the longitudinal axis thereof, saidsupport means having a resilient restoring force, and a vibrationgenerator operatively connected to said conduit including an unbalancedmass mounted for rotation about an axis for imparting vibrations to saidconduit having a component transverse to the longitudinal axis of saidconduit and a component parallel to the longitudinal axis of saidconduit, the rotational axis of said unbalanced mass forming an acuteangle with the longitudinal axis of said conduit to cyclically vibrateand deform the cross-section thereof.

References Cited in the file of this patent UNITED STATES PATENTS807,423 Fern Dec. 12, 1905 1,989,777 Wettlaufer Feb. 5, 1935 2,143,610Muller Jan. 10, 1939 2,398,455 Unger Apr. 16, 1946 2,682,3 8 Hurst July29, 1954 FOREIGN PATENTS 897,231 Germany Nov. 19, 1953 904,761 GermanyFeb. 22, 1954 489,210 Great Britain July 21, 1938

